This project extends Dr. Fergusons research into oxidative stress as a unifying mechanism connecting environmental contaminant exposure to adverse reproductive and pregnancy outcomes. The concept for this project was presented to the Epidemiology Branch in August of 2016 and received approval. We have additionally made progress toward selecting a laboratory for analysis of oxidative stress measures, and toward identifying subjects and specific time points of sample collection that we will utilize in the present study. Over the next calendar year we anticipate completion of urinary oxidative stress biomarker analysis and publishing the primary findings from this study.